Low-water alarm



May 13, 1924; masxi B. W. KABEL. ET AL.

LOW WATER ALARM Filed May`25. 1920 (Il I i locomotive boiler.

NITED TTES FFEE.

BYERS W. KADEL, JOHN A. PILCHER, AND HARRY W. CODDINGTON, OF RONOKE,

f VIRGINIA.

LOW-WATER ALARM.

Application filed May 25, 1920. Serial No. 384,018.

To all whom t may concern.'

Be it known that we, Bruns W. KABEL, JOHN A. PILoHnR, and HARRY W. ConDING- TON, citizens of the United States, residing at Roanoke, in the county of Roanoke and State of Virginia, have invented certain new and useful Improvements in Low-1V ater Alarms, of which the following is a specification.

This invention relates to low water alarms of the thermostatic type for steam boilers and is intended for use primarily with low water alarms of the general type, disclosed in our earlier Patents No. 1,181,316 of May 2, 1916 and No. 1,127,010 of Feb. 2, 1915. Thevpresent invention has among' its objects to provide means tor making such devices more sensitive and for increasing their range of operation. With such objects in view the invention consists ot' the format-ion, combination,and arrangement of parts as will be herein described and finally claimed.

In the drawings, Figure 1 is a' vertical sec-tional view tal-Ten through a portion of a low water alarm in which the principles of the present invention are embodied. Figure 2 is a transverse sectional view through the bafile. this view being' taken onthe line 2 2 of Figure 1. Figure 3 is an end elevational view of the boiler fitting. this view being seen from the direction of the arrow in Figure 1 but with the screw plug` removed from the boiler iitting. Figure 4: is a similar view but with the screw plug is place. Figure 5 is an end elevational view of the baffle, removed from the alarm. Figure 6 is a general view of the application of a low water alarm of the thermostatic type to a The invention is not shown in detail in this view, the view being supplied for the purpose of obtaining a ready understanding of the `general operation of low water alarms of this type. The boiler-connectmgz` end of the mechanism. as

i such devices is fully set 'forth in our earlier patents, and it will not be necessary to go at length into these phases at this time.

In the present drawings, 10 represents I the shell'of a boiler, beneath which is the steam and water space. A low water alarm fitting or header 11 is attached to the shell of the boiler by means of the ball joint 13 and bolts 141. The tting 11 is hollow and communicates at its lower end with the steam and water space of the boiler through the drop pipe 15. Thislatter is carried down into the boiler to a point beneath the normal water level, the termination of this pipe determining the stage where the alarm will sound. The expansion element 16 is attached to a branch of the fittino 11 by means of the spanner joint 17. The expansion element is thus, through the fitting 11 and drop pipe 15, in open fluid communication with the steam and water space of the boiler. The passageways in the expansion element and in the fitting` 11 are usually made of liberal size to obviate stoppage and to permit of ready cleansing. To this latter end also the lower, or boiler end ot the fitting 11 is made with a 'full diameter opening, into which is then screwed the reducer 18. Into this latter is screwed the drop pipe 15 which is o1 reduced diameter. lt has been found that by making' this drop pipe ot less diameter than the connected parts of the alarm, the circulation of' water from the boiler will be reduced and consequently the water held in the 'expansion element at times other than in cases of low water will be of lower temperature with a consequent extension of the operative rauge'of the device. Also, the reduced size of the drop pipe causes some slight lag to the drop ot the water when. the lower end ot the' drop pipe is uncovered. r)This action tends to obviate soundings of the alarm due to a momentary surge of the water in a locomotive boiler.

The fitting` 11 is provided with an opening 19 in axial alignment with the cavity of the expansion element 16. This is provided primarily for the purpose of cleaning' the expansion element and is normally closed by the screw plugl 9.0. lt has been found by experiment that by inserting a series of' baffles or oholres in the lower or boiler end of the expansion element and in the fitting 11 the circulation oi the water is still further reduced and the range of the device greatly extended. Accordingly, there has been inserted through the opening 19 the series of chokes 24:, which are connectedby an integral rod Q1. These are formed in a single unit and are inserted through the opening CFI 197 there being an outer stop 22 that seats against a shoulder 23 of the fittings 11. The screw plug 2O when applied to the opening 19 holds the baffles in position.

The baflle itself is made With three active discs or choke members 24, through the upper edge of each of which is a steam opening 25 with a similar Water opening 26 at the bottom edge of each. Thus as long as the expansion element is filled with Water the spaced discs break up the circulation of'Water Within the several tubes and prevent the bodily dropping of the column of Water When the end of the drop pipe is momentarily uncovered. But when an actual case of low Water occurs the Water will immediately run back into the boiler.l the steam rising through the holes 25 while at the same time the water is retreating through the holes 26. The outer disc or stop 22 has a notch or keyway 27 which registers with a suitable doWel in the metal of the fitting 11 to insure the correct positioning of the baffle in the passageway. ein eye 28 is also provided for aid in removing the baflle.

There has thus been described an embodiment of the present invention. Other embodiments are possible Wit-hin the scope of the appended claims Without departing from the spirit thereof.

lVhat is claimed is:

l. In a loiv water alarm of the thermostatic type, the combination with a hollow fitting attached to the shell of the boiler and in open fluid comniunication with' the steam and Water space thereof of an expansion element attached to the outer end of said fitting and in fluid communication with the interior thereof, the outer end of said eX- pansion element being normally closed, and a choke in the expansion element near the inner end thereof.

2. In a low Water alarm of the thermostatic type, an expansion element, the same having one end in communication With the steam and Water space of the boiler, and a series of chokes in the expansion element near the boiler-communicating end thereof, said chokes being spaced from each other.

3. In a low Water alarm of the thermostatic type, a fitting attached to the boiler shell, and in open fluid communication With thek steam and Water space of the boiler, an expansion element lying in a line at an angle With the cavity of said fitting and approaching the horizontal, the same having one end in communication with the steam and Water space of the boiler through the cavity of the said fitting, and means near the inner end of the expansion element for restricting thev flow of Water, butarranged to freely admit of the passage of steam.

Lf. In a low Water alarm of the thermostatic type, a fitting attached to the shell of the boiler and in open fluid communication With the steam and Water space therein, an expansion element attached to and in communication at its inner end With the outer end of said fitting, the said expansion element being normally filled with water, and means for restricting the local circulation of Water Within the expansion element, said. meansr embodying a. choke near the lower end of the expansion element having an opening therein, the area of said opening being of less extent than the area of the communication of said fitting with the interior of the boiler.

5. In a loiv Water alarm of the thermostatic type, an expansion element of tubular form and a choke in the same, said choke comprising a plate disposed across the cavity of the tube with diametrically oppositely arranged openings'in the plate.

6. In a lon' ivater alarm of the thermostatic type, a fitting attached to the boiler and in open fluid communication with the interior thereof, an expansion element attached to the outer end of said fitting and in fluid communication with the cavity thereof, a normally closed opening in the fitting in axial alignment with the cavity of the expansion element, and an expansion element choke Within the inner end of the eX- pansion element, said choke being removed through the said opening.

7. In a low Water alarm of the thermostatic type, an expansion element having a fluid channel therein, a fitting connected to the expansion element, the same also having a fluid channel therein and comprising means for connecting the fluid channel of the expansion element with. the steam or Water cavity of the boiler, an opening leading from the atmosphere into one of said fluid channels, means for normally closing said opening and means for restricting the circulation of fluid between the channel of the expansion element and the cavity of the boiler, the same embodying a choke removable through the said opening.

8. In a low wate alarm of the thermostatic type, an expansion element having a fluid channel therein, a fitting connected to the expansion element, the same also having a fluid channel therein and comprising means for connecting the fluid channel of the expansion element .with the steam or Water cavity of thel boiler, an opening leading from the atmospliere into one of said 'fluid channels, means for normally closing said opening and means for restricting the circulation of fluid between the channel of the expansion element and the cavity of the boiler, the same embodying a choke insertable through the said opening and arranged to be anchored by the said closing means.

9. In a low Water alarm of the thermostatic type, an expansion element, a connection between the expansion element and the boiler, the same having a fluid passageway the said closing means for holding the baie therethrough adapted to connect the cavity in position.

of the expansion element with the cavity In testimony whereof We ax our signa- 10 of the boiler, an opening in the said oon tures.

5 neotion and closing means therefor', a bafe BYERS W. KADEL. in the iuid passageway insertablethrough JOHN A. PILCHER. the said opening, and means oooperable with HARRY W. CODDINGTON. 

